Sedimentation and floatation wastewater treatment device with a heater

ABSTRACT

A combined sedimentation and pressure floatation wastewater treatment tank includes a tank body, a sedimentation treatment device and a pressure floatation treatment device. The tank body contains a predetermined amount of wastewater for treatment. The sedimentation treatment device is operated to remove relatively heavier sludge from the wastewater by sedimentation treatment, and the pressure floatation treatment device is operated to remove relatively lighter sludge from the initially treated wastewater by pressure floatation treatment. In operation, the wastewater is initially treated by the sedimentation treatment device and is further treated by the pressure floatation treatment device. Alternatively, the wastewater is initially treated by the pressure floatation treatment device and is further treated by the sedimentation treatment device.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 12/639,066, filed Dec. 16, 2009, now U.S. Pat. No. 8,524,089,which is hereby incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a sedimentation and pressure floatationwastewater treatment device with a heater. More particularly, thepresent invention relates to a sedimentation arrangement and pressurefloatation arrangement incorporated in a single wastewater treatmenttank for providing a dual treatment function.

2. Description of the Related Art

In general, wastewater treatment covers several wastewater treatmentmethods, according to physical properties, for the removal of solidsludge contained in the wastewater. If the sludge is lighter, a pressurefloatation method is employed and implemented in a wastewater pressurefloatation treatment tank or facilities, for example. If solids andlarge particles of the sludge are heavier, a sedimentation method isemployed and implemented in a wastewater sedimentation treatment tank orfacilities, for example. However, both the pressure floatation methodand the sedimentation method are well-developed wastewater treatmenttechnologies.

For example, Taiwanese Utility Model Patent No. 324684, entitled“Oil-stock Tank for Pressure Floatation Treatment,” discloses anoil-stock structure of a pressure floatation tank, and Taiwanese UtilityModel Patent No. 265409, entitled “Improved Oil-stock Tank Structure,”discloses an improved oil-stock tank structure for pressure floatationtreatment.

U.S. Pat. No. 5,021,165, entitled “Oil and Water Separating System withHydrocyclone and Floatation Device, ” discloses a pressure floatationmethod for oil and water separation treatment. U.S. Pat. No. 4,448,681,entitled “Floatation Arrangement,” discloses a pressure floatationarrangement. U.S. patent application publication No. 20080006577,entitled “Method and Apparatus for Wastewater Treatment usingNitrogen/Phosphorous Removal Process Combined with Floatation Separationof Activated Sludge,” discloses a pressure floatation separation methodand an apparatus thereof. Each of the above-mentioned Taiwanese and USpatent application publications and issued patents is incorporatedherein by reference for purposes including, but not limited to,indicating the background of the present invention and illustrating thestate of the art.

As a matter of fact, in wastewater treatment processes, there aregrease, organic solvents and other equivalent waste materials containedin the wastewater. In some circumstances, changes of wastewater sludgeproperties will result in enlarging or shrinking sizes of flocscontained in the wastewater. Simply employing either of the pressurefloatation method or the sedimentation method cannot achieve thecomplete removal of the solid sludge contained in the wastewater.Consequently, a great amount of remnant sludge remaining in the wastewater treatment tank will overflow into the environment. Hence, theremnant sludge will affect the quality of the treated wastewater whenprocessing a single treatment selected from the pressure floatationmethod and the sedimentation method.

As has been discussed above, these patents do not disclose a combineddevice for incorporating different wastewater treatment methods.However, the single treatment of either the pressure floatation methodor the sedimentation method cannot achieve the complete removal of thesolid sludge contained in the wastewater. Hence, there is a need ofimproving the conventional pressure floatation method and theconventional sedimentation method for enhancing the efficiency ofremoving the solid sludge.

As is described in greater detail below, the present invention providesa combined sedimentation and pressure floatation wastewater treatmenttank. A sedimentation arrangement and pressure floatation arrangementincorporated in a single wastewater treatment tank provides a dualtreatment function in such a way as to mitigate and overcome the aboveproblem.

SUMMARY OF THE INVENTION

The primary objective of this invention is to provide a combinedsedimentation and pressure floatation wastewater treatment tank. Asedimentation arrangement and pressure floatation arrangementincorporated in a single wastewater treatment tank provides a dualtreatment function. Accordingly, the wastewater treatment tank issuccessful in treating wastewater by sedimentation and pressurefloatation.

The combined sedimentation and pressure floatation wastewater treatmenttank in accordance with an aspect of the present invention includes atank body, a sedimentation treatment device, a heater unit and apressure floatation treatment device. The tank body contains apredetermined amount of wastewater for treatment. The sedimentationtreatment device is operated to remove relatively heavier sludge fromthe wastewater by the sedimentation treatment, the pressure floatationtreatment device is operated to remove relatively lighter sludge fromthe initially treated wastewater by the pressure floatation treatment,and the heater unit is operated to heat the wastewater and the sludge.In operation, the wastewater is initially treated by the sedimentationtreatment device and is further treated by the pressure floatationtreatment device. Alternatively, the wastewater is initially treated bythe pressure floatation treatment device and is further treated by thesedimentation treatment device.

In a separate aspect of the present invention, the sedimentationtreatment device is arranged at a lower portion of the wastewatertreatment tank.

In a further separate aspect of the present invention, the sedimentationtreatment device includes a plurality of inclined walls.

In yet a further separate aspect of the present invention, thesedimentation treatment device connects with a first sludge scrapermachine operated to scrape and discharge sludge sediments from aninterior of the wastewater treatment tank.

In yet a further separate aspect of the present invention, the pressurefloatation treatment device is arranged at an upper portion of thewastewater treatment tank.

In yet a further separate aspect of the present invention, the pressurefloatation treatment device includes an air compressor unit.

In yet a further separate aspect of the present invention, the pressurefloatation treatment device further includes a second sludge scrapermachine operated to scrape and discharge floated sludge from theinterior of the wastewater treatment tank.

In yet a further separate aspect of the present invention, the pressurefloatation treatment device further includes an additional sedimentationtreatment unit.

In yet a further separate aspect of the present invention, theadditional sedimentation treatment unit connects with a side of thepressure floatation treatment device.

In yet a further separate aspect of the present invention, the heaterunit is provided with a heat sensor to measure the wastewater.

Further scope of the applicability of the present invention will becomeapparent from the detailed description given hereinafter. However, itshould be understood that the detailed description and specificexamples, while indicating preferred embodiments of the invention, aregiven by way of illustration only, since various modifications willbecome apparent to those skilled in the art from this detaileddescription.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description given hereinbelow and the accompanying drawingswhich are given by way of illustration only, and thus are not limitativeof the present invention, and wherein:

FIG. 1 is a structurally schematic view of a combined sedimentation andpressure floatation wastewater treatment tank in accordance with a firstpreferred embodiment of the present invention.

FIG. 2 is a perspective schematic view of an additional sedimentationtreatment unit applied in the combined sedimentation and pressurefloatation wastewater treatment tank in accordance with the firstpreferred embodiment of the present invention, depicted in FIG. 1.

FIG. 3 is a structurally schematic view, similar to FIG. 1, of thecombined sedimentation and pressure floatation wastewater treatment tankoperated in a reverse direction of wastewater treatment in accordancewith a second preferred embodiment of the present invention.

FIG. 4 is a side view of the combined sedimentation and pressurefloatation wastewater treatment tank in accordance with a thirdpreferred embodiment of the present invention.

FIG. 5 is another side view of the wastewater treatment tank inaccordance with the third preferred embodiment of the present invention.

FIG. 6 is a top view of the wastewater treatment tank in accordance withthe third preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

It is noted that a combined sedimentation and pressure floatationwastewater treatment tank in accordance with the preferred embodimentsof the present invention can be applicable to a wide variety ofwastewater treatment systems or the like. By way of example, thecombined sedimentation and pressure floatation wastewater treatment tankmay incorporate with a single sedimentation treatment tank or a singlepressure floatation treatment tank.

FIG. 1 shows a structurally schematic view of a combined sedimentationand pressure floatation wastewater treatment tank in accordance with afirst preferred embodiment of the present invention. With continuedreference to FIG. 1, the combined sedimentation and pressure floatationwastewater treatment tank 1 in accordance with the preferred embodimentof the present invention includes a tank body 10, a sedimentationtreatment device 2, a heater unit 200 and a pressure floatationtreatment device 3. The wastewater treatment tank 1 provides thefunctions of first sedimentation and second pressure floatationtreatment, or providing the functions of first pressure floatationtreatment and second sedimentation, as will be discussed in greaterdetail subsequently. In addition, the combined sedimentation andpressure floatation wastewater treatment tank 1 further provides afunction of heating the wastewater and the sludge by the heater unit200.

Still referring to FIG. 1, the tank body 10 of the first preferredembodiment may have any shape or size desired, but it must permitaccommodating the sedimentation treatment device 2, the heater unit 200and the pressure floatation treatment device 3. The tank body 10 isformed to incorporate the sedimentation treatment device 2 with thepressure floatation treatment device 3, such that the wastewatertreatment tank 1 can provide a dual function of sedimentation andpressure floatation treatment, or pressure floatation and sedimentationtreatment. In a preferred embodiment, the tank body 10 is formed from asingle tank body, which is not limitative of the present invention.

Still referring to FIG. 1, the tank body 10 of the first preferredembodiment is formed with at least one wastewater inlet (not labeled),at least one treated water outlet (not labeled) and at least one sludgeoutlet (not labeled) which are formed from known structures in the art.The constructions of the wastewater inlet, the treated water outlet andthe sludge outlet have a known configuration, and the detaileddescriptions may be omitted. The number and positions of the wastewaterinlet, the treated water outlet and the sludge outlet are arrangedaccording to design needs.

Referring again to FIG. 1, untreated wastewater flows into the tank body10 via the wastewater inlet (as best shown in the direction indicated byarrow “a” in FIG. 1) and circulates in the tank body 10. Thesedimentation treatment device 2, the heater unit 200 and the pressurefloatation treatment device 3 are equipped in the tank body 10 to treatthe wastewater, and the treated water is discharged from the treatedwater outlet. Meanwhile, the heater unit 200 electrically connected witha heat sensor 201 is operated to heat or warm the wastewater and thesludge in a predetermined temperature. Furthermore, the sludge removedfrom the wastewater is discharged from the sludge outlet.

With continued reference to FIG. 1, in the first preferred embodiment,the sedimentation treatment device 2 and the heater unit 200 arearranged at a lower portion of wastewater treatment tank 1 which is notlimitative of the present invention. The sedimentation treatment device2 includes a plurality of inclined walls 20 formed with a predeterminedangle, and is operated to remove relatively heavier sludge from thewastewater by the sedimentation treatment with the inclined walls 20. Inthe sedimentation treatment device 2, the wastewater may flow upwardalong the inclined walls 20, as best shown in the direction indicated byarrow “b” in FIG. 1,and the relatively heavier sludge will slow down.Meanwhile, the sedimentation of the heavier sludge occurs andaccumulates on the inclined walls 20, such that the sludge sediment willflow down along the inclined walls 20. In a preferred embodiment, theheater unit 200 is operated to heat the sludge in the sedimentationtreatment.

Still referring to FIG. 1, the sedimentation treatment device 2 furtherincludes a first sludge scraper machine 21 arranged at a bottom of thewastewater treatment tank 1. The sedimentation treatment device 2connects with the first sludge scraper machine 21 operated to scrape anddischarge the sludge sediments from an interior of the wastewatertreatment tank 1 via the sludge outlet, which can be achieved in theknown manner, so that the detailed descriptions may be omitted. In apreferred embodiment, the heater unit 200 is operated to heat or warmthe sludge or grease sediments in the predetermined temperature at thebottom of the wastewater treatment tank 1 in order to enhance thedischarge of the sludge sediments.

Still referring to FIG. 1, the wastewater still remains with relativelylighter sludge, impurities or grease even though the relatively heaviersludge has been removed by sedimentation treatment. Subsequently, theinitially treated wastewater is guided to the pressure floatationtreatment device 3, as best shown in the direction indicated by arrow“b” in FIG. 1, for further removing the lighter sludge, impurities andgrease from the initially treated wastewater.

Still referring to FIG. 1, in the first preferred embodiment, thepressure floatation treatment device 3 is arranged at an upper portionof wastewater treatment tank 1, which is not limitative of the presentinvention. The pressure floatation treatment device 3 is operated toremove lighter sludge, impurities, grease and other remnants from theinitially treated wastewater by the pressure floatation treatment. Inoperation, the lighter sludge, impurities, grease and other remnantswill float on the wastewater of the wastewater treatment tank 1.

With continued reference to FIG. 1, the pressure floatation treatmentdevice 3 includes an air compressor unit 30, a first pressurized watersprayer 301 and a second pressurized water sprayer 302. The firstpressurized water sprayer 301 and the second pressurized water sprayer302 are arranged at a bottom portion of the pressure floatationtreatment device 3. The air compressor unit 30 is operated to mixcompressed air with water, and to add the pressurized water into thewastewater by spraying or jetting the pressurized water, as best shownin the direction indicated by arrows “d” in FIG. 1. The pressurizedwater can bring the lighter sludge, impurities and grease to the upperportion of the pressure floatation treatment device 3 and to float onthe wastewater surface. Finally, the completely treated water isdischarged from the pressure floatation treatment device 3, as bestshown in the direction indicated by a series of arrows “c” in FIG. 1.

Referring again to FIG. 1, in the first preferred embodiment, thepressure floatation treatment device 3 further includes a second sludgescraper machine 31 arranged at the top portion of the pressurefloatation treatment device 3. The pressure floatation treatment device3 operated to scrape and discharge floated sludge from the interior ofthe wastewater treatment tank 1. Finally, the floated sludge will bedischarged from the pressure floatation treatment device 3 via thesludge outlet.

Still referring to FIG. 1, in the first preferred embodiment, thepressure floatation treatment device 3 further includes an additionalsedimentation treatment unit 32 which connects with a side of thepressure floatation treatment device 3. The secondly treated wastewateris guided from the pressure floatation treatment device 3 to theadditional sedimentation treatment unit 32, as best shown in thedirection indicated by a series of arrows “c” in FIG. 1. Finally, thecompletely treated wastewater will be discharged from the pressurefloatation treatment device 3 via the treated water outlet to exterior.

FIG. 2 shows a perspective schematic view of the additionalsedimentation treatment unit applied in the combined sedimentation andpressure floatation wastewater treatment tank in accordance with thefirst preferred embodiment of the present invention. Referring to FIG.2, the additional sedimentation treatment unit 32 includes a pluralityof inclined walls 321, wastewater inlets 322, treated water outlets 323and sludge outlets 324, which are not limitative of the presentinvention.

Referring again to FIGS. 1 and 2, the sedimentation treatment unit 32 isoperated to further remove the relatively heavier remnant sludgeremaining in the secondly treated wastewater discharged from thepressure floatation treatment device 3, as best shown in the directionsindicated by curved arrows in FIG. 2. The wastewater may flow upwardalong the inclined walls 321, and the relatively heavier remnant sludgewill slow down. Meanwhile, the sedimentation of the heavier remnantsludge occurs and accumulates on the inclined walls 321, such that theremnant sludge sediment will flow down along the inclined walls 321 toachieve the sedimentation treatment. The completely treated water can bedischarged from the treated water outlets 323, as best shown in thedirections indicated by upward arrows in FIG. 2. Correspondingly, theremnant sludge sediments can be discharged from the sludge outlets 324,as best shown in the directions indicated by downward arrows in FIG. 2,to the exterior.

Still referring to FIGS. 1 and 2, the treated water can be dischargedfrom the sedimentation treatment unit 32 to the exterior, as best shownthe direction indicated by a series of arrows “c” in FIG. 1. Finally,the remnant sludge sediments can be discharged from the interior of thewastewater treatment tank 1 via the sludge outlet, which can be achievedin the known manner so that the detailed descriptions may be omitted.

With continued reference to FIGS. 1 and 2, in the wastewater treatmenttank 1 in accordance with the first preferred embodiment of the presentinvention, the wastewater is firstly treated in the sedimentationtreatment device 2 with the heater unit 200, and the treated wastewateris further treated in the pressure floatation treatment device 3 toprovide a dual treatment function of wastewater treatment.

FIG. 3 shows a structurally schematic view of the combined sedimentationand pressure floatation wastewater treatment tank operated in a reversedirection of wastewater treatment in accordance with a second preferredembodiment of the present invention. Reference numerals of the secondembodiment of the present invention have applied the identical numeralsof the first embodiment, as best shown in FIG. 1. The construction ofthe wastewater treatment tank in accordance with the second embodimenthas a similar configuration and a same function as those of the firstembodiment, so that the detailed descriptions may be omitted.

Referring to FIG. 3, in comparison with the first embodiment, thewastewater treatment tank 1 in accordance with the second preferredembodiment of the present invention is operated in a reverse treatmentprocess. In operation, untreated wastewater flows into the tank body 10via the wastewater inlet. Firstly, the untreated wastewater passesthrough the sedimentation treatment unit 32 (as best shown in thedirection indicated by a series of arrows c′ in FIG. 3) for preliminarysedimentation treatment. Secondly, the wastewater flows to the pressurefloatation treatment device 3 (as best shown in the direction indicatedby a series of arrows c′ in FIG. 3) for pressure floatation treatment bypressurized water, as best shown in the direction indicated by arrows din FIG. 3. Thirdly, the wastewater flows downward to the sedimentationtreatment device 2 and the heater unit 200 (as best shown in thedirection indicated by arrows b′ in FIG. 3) for sedimentation treatment.Finally, the completely treated water is discharged from thesedimentation treatment device 2 via the treated water outlet, as bestshown in the direction indicated by a series of arrows a′ in FIG. 3, tothe exterior.

With continued reference to FIG. 3, in the wastewater treatment tank 1in accordance with the second preferred embodiment of the presentinvention, the wastewater is firstly treated in the pressure floatationtreatment device 3, and is further treated in the sedimentationtreatment device 2 with the heater unit 200 to provide a dual treatmentfunction of wastewater treatment.

FIGS. 4 through 6 show side and top views of the wastewater treatmenttank in accordance with a third preferred embodiment of the presentinvention. Reference numerals of the third embodiment of the presentinvention have applied the identical numerals of the first and secondembodiments, as best shown in FIGS. 1 and 3. The construction of thewastewater treatment tank in accordance with the third embodiment has asimilar configuration and a same function as those of the first andsecond embodiments, so that the detailed descriptions may be omitted.

Referring to FIGS. 4 through 6, the wastewater treatment tank 1 inaccordance with the third preferred embodiment of the present inventionincludes a tank body 10, a sedimentation treatment device 2, at leasttwo heater units 200 and a pressure floatation treatment device 3. Inthe third embodiment, the heater units 200 are provided at differentpositions to heat the waste water and the sludge at an upper portion anda lower portion of the tank body 10, for example. By way of example, theheater unit 200 is arranged on an inner wall of the tank body 10 andsurrounds the lower portion of the tank body 10. Correspondingly, theheater unit 200′ is selectively arranged on an outer circumferentialwall of a pipe line at the upper portion of the tank body 10 adjacent tothe pressure floatation treatment device 3 for heating or warming thefloated sludge. The heater unit 200 includes a steam inlet 211 and asteam outlet 212 connected with an interior of the heater unit 200. Inoperation, the high-temperature steam can be supplied into the heaterunit 200 via the steam inlet 211 from a heat source (e.g. steamer) andthe relatively low-temperature steam can be discharged from the steamoutlet 212 and then supplied to the heat source. Ina preferredembodiment, the heater unit 200 is provided with at least one heatsensor 201 to measure the wastewater for controlling the heatingoperation of the heater unit 200 or heat source.

Although the invention has been described in detail with reference toits presently preferred embodiment(s), it will be understood by one ofordinary skill in the art that various modifications can be made withoutdeparting from the spirit and the scope of the invention, as set forthin the appended claims.

What is claimed is:
 1. A combined sedimentation and pressure floatationwastewater treatment apparatus, comprising: a tank body containingwastewater; a sedimentation treatment device including a plurality ofinclined walls and operated to remove relatively heavier sludge from thewastewater by sedimentation treatment, with the sedimentation treatmentdevice arranged at a lower portion of the tank body; a pressurefloatation treatment device operated to remove relatively lighter sludgefrom the wastewater by pressure floatation treatment, with the pressurefloatation treatment device arranged at an upper portion of the tankbody above the inclined walls; means for alternately flowing thewastewater from the lower portion to the upper portion of the tank bodyto be initially treated by the sedimentation treatment device and theinitially-treated wastewater to be further treated by the pressurefloatation treatment device above the inclined walls and reverselyflowing the wastewater from the upper portion to the lower portion ofthe tank body to be initially treated by the pressure floatationtreatment device and the initially-treated wastewater to be furthertreated by the sedimentation treatment device below the pressurefloatation treatment device; and at least one heater unit operated toheat the wastewater and sludge in the sedimentation treatment and thepressure floatation treatment.
 2. The combined sedimentation andpressure floatation wastewater treatment apparatus as defined in claim1, wherein the sedimentation treatment device connects with a sludgescraper machine operated to scrape sludge sediments or the pressurefloatation treatment device includes a sludge scraper machine operatedto scrape floated sludge.
 3. The combined sedimentation and pressurefloatation wastewater treatment apparatus as defined in claim 1, whereinthe pressure floatation treatment device further includes an additionalsedimentation treatment unit.
 4. The combined sedimentation and pressurefloatation wastewater treatment apparatus as defined in claim 3, whereinthe additional sedimentation treatment unit connects with a side of thepressure floatation treatment device.
 5. The combined sedimentation andpressure floatation wastewater treatment apparatus as defined in claim1, wherein the heater unit is arranged on an inner wall of the tankbody.
 6. The combined sedimentation and pressure floatation wastewatertreatment apparatus as defined in claim 1, wherein the heater unit isarranged on an outer circumferential wall of a pipe line at the upperportion of the tank body adjacent to the pressure floatation treatmentdevice.
 7. Wastewater treatment method comprising: flowing wastewaterinto a tank body into a sedimentation treatment device with inclinedwalls arranged at a lower portion of the tank body removing relativelyheavier sludge from the wastewater by sedimentation treatment and fromthe sedimentation treatment device into a pressure floatation treatmentdevice arranged at an upper portion of the tank body above the inclinedwalls removing relatively lighter sludge from the wastewater by pressurefloatation with heating the wastewater and the sludge at a predeterminedtemperature and reversing flow of the wastewater into the upper portionof the tank body into the pressure floatation treatment device removingrelatively lighter sludge from the wastewater by pressure floatation andfrom the pressure floatation treatment device into the lower portion ofthe tank body into the inclined walls of the sedimentation treatmentdevice removing relatively heavier sludge from the wastewater bysedimentation treatment with heating the wastewater and the sludge at apredetermined temperature.
 8. The wastewater treatment method of claim 7further comprising: forming at least one wastewater inlet in the tankbody; wherein flowing wastewater into the tank body into thesedimentation treatment device comprises flowing the wastewater into theat least one wastewater inlet; and wherein flowing the wastewater fromthe pressure floatation treatment device into the sedimentationtreatment device includes flowing the wastewater out the at least onewastewater inlet.
 9. The wastewater treatment method of claim 8 furthercomprising: spraying pressured water at a bottom portion of the pressurefloatation treatment device and above the inclined walls.
 10. Thewastewater treatment method of claim 7 further comprising: supplyinghigh-temperature steam via at least one steam inlet and dischargingrelatively low-temperature steam from at least one steam outlet.
 11. Thewastewater treatment method of claim 10 further comprising:communicating the steam inlet and the steam outlet with at least oneheat source.
 12. The wastewater treatment method of claim 7 furthercomprising: providing at least one heater unit to heat an upper or lowerportion of the tank body and controlling with a heat sensor.